kernel/linux.git/tools/perf/builtin-record.c, branch v6.6.148

perf record: skip synthesize event when open evsel failed

2026-01-11T14:21:19+00:00

[ Upstream commit 163e5f2b96632b7fb2eaa965562aca0dbdf9f996 ] When using perf record with the `--overwrite` option, a segmentation fault occurs if an event fails to open. For example: perf record -e cycles-ct -F 1000 -a --overwrite Error: cycles-ct:H: PMU Hardware doesn't support sampling/overflow-interrupts. Try 'perf stat' perf: Segmentation fault #0 0x6466b6 in dump_stack debug.c:366 #1 0x646729 in sighandler_dump_stack debug.c:378 #2 0x453fd1 in sigsegv_handler builtin-record.c:722 #3 0x7f8454e65090 in __restore_rt libc-2.32.so[54090] #4 0x6c5671 in __perf_event__synthesize_id_index synthetic-events.c:1862 #5 0x6c5ac0 in perf_event__synthesize_id_index synthetic-events.c:1943 #6 0x458090 in record__synthesize builtin-record.c:2075 #7 0x45a85a in __cmd_record builtin-record.c:2888 #8 0x45deb6 in cmd_record builtin-record.c:4374 #9 0x4e5e33 in run_builtin perf.c:349 #10 0x4e60bf in handle_internal_command perf.c:401 #11 0x4e6215 in run_argv perf.c:448 #12 0x4e653a in main perf.c:555 #13 0x7f8454e4fa72 in __libc_start_main libc-2.32.so[3ea72] #14 0x43a3ee in _start ??:0 The --overwrite option implies --tail-synthesize, which collects non-sample events reflecting the system status when recording finishes. However, when evsel opening fails (e.g., unsupported event 'cycles-ct'), session->evlist is not initialized and remains NULL. The code unconditionally calls record__synthesize() in the error path, which iterates through the NULL evlist pointer and causes a segfault. To fix it, move the record__synthesize() call inside the error check block, so it's only called when there was no error during recording, ensuring that evlist is properly initialized. Fixes: 4ea648aec019 ("perf record: Add --tail-synthesize option") Signed-off-by: Shuai Xue Signed-off-by: Namhyung Kim Signed-off-by: Sasha Levin

perf record: Fix incorrect --user-regs comments

2025-06-19T13:28:28+00:00

[ Upstream commit a4a859eb6704a8aa46aa1cec5396c8d41383a26b ] The comment of "--user-regs" option is not correct, fix it. "on interrupt," -> "in user space," Fixes: 84c417422798c897 ("perf record: Support direct --user-regs arguments") Reviewed-by: Ian Rogers Signed-off-by: Dapeng Mi Cc: Adrian Hunter Cc: Alexander Shishkin Cc: Andi Kleen Cc: Ingo Molnar Cc: Kan Liang Cc: Namhyung Kim Cc: Peter Zijlstra Link: https://lore.kernel.org/r/20250403060810.196028-1-dapeng1.mi@linux.intel.com Signed-off-by: Arnaldo Carvalho de Melo Signed-off-by: Sasha Levin

perf record: Fix debug message placement for test consumption

2024-06-12T09:12:18+00:00

[ Upstream commit 792bc998baf9ae17297b1f93b1edc3ca34a0b7e2 ] evlist__config() might mess up the debug output consumed by test "Test per-thread recording" in "Miscellaneous Intel PT testing". Move it out from between the debug prints: "perf record opening and mmapping events" and "perf record done opening and mmapping events" Fixes: da4062021e0e6da5 ("perf tools: Add debug messages and comments for testing") Closes: https://lore.kernel.org/linux-perf-users/ZhVfc5jYLarnGzKa@x1/ Reported-by: Arnaldo Carvalho de Melo Signed-off-by: Adrian Hunter Tested-by: Arnaldo Carvalho de Melo Cc: Ian Rogers Cc: Jiri Olsa Cc: Namhyung Kim Link: https://lore.kernel.org/r/20240411075447.17306-1-adrian.hunter@intel.com Signed-off-by: Arnaldo Carvalho de Melo Signed-off-by: Sasha Levin

perf record: Move setting tracking events before record__init_thread_masks()

2024-06-12T09:12:18+00:00

[ Upstream commit 1285ab300d598ead593b190af65a16f4b0843c68 ] User space tasks can migrate between CPUs, so when tracing selected CPUs, sideband for all CPUs is needed. In this case set the cpu map of the evsel to all online CPUs. This may modify the original cpu map of the evlist. Therefore, need to check whether the preceding scenario exists before record__init_thread_masks(). Dummy tracking has been set in record__open(), move it before record__init_thread_masks() and add a helper for unified processing. The sys_perf_event_open invoked is as follows: # perf --debug verbose=3 record -e cpu-clock -D 100 true Opening: cpu-clock ------------------------------------------------------------ perf_event_attr: type 1 (PERF_TYPE_SOFTWARE) size 136 config 0 (PERF_COUNT_SW_CPU_CLOCK) { sample_period, sample_freq } 4000 sample_type IP|TID|TIME|PERIOD|IDENTIFIER read_format ID|LOST disabled 1 inherit 1 freq 1 sample_id_all 1 exclude_guest 1 ------------------------------------------------------------ sys_perf_event_open: pid 10318 cpu 0 group_fd -1 flags 0x8 = 5 sys_perf_event_open: pid 10318 cpu 1 group_fd -1 flags 0x8 = 6 sys_perf_event_open: pid 10318 cpu 2 group_fd -1 flags 0x8 = 7 sys_perf_event_open: pid 10318 cpu 3 group_fd -1 flags 0x8 = 9 sys_perf_event_open: pid 10318 cpu 4 group_fd -1 flags 0x8 = 10 sys_perf_event_open: pid 10318 cpu 5 group_fd -1 flags 0x8 = 11 sys_perf_event_open: pid 10318 cpu 6 group_fd -1 flags 0x8 = 12 sys_perf_event_open: pid 10318 cpu 7 group_fd -1 flags 0x8 = 13 Opening: dummy:u ------------------------------------------------------------ perf_event_attr: type 1 (PERF_TYPE_SOFTWARE) size 136 config 0x9 (PERF_COUNT_SW_DUMMY) { sample_period, sample_freq } 1 sample_type IP|TID|TIME|IDENTIFIER read_format ID|LOST disabled 1 inherit 1 exclude_kernel 1 exclude_hv 1 mmap 1 comm 1 enable_on_exec 1 task 1 sample_id_all 1 exclude_guest 1 mmap2 1 comm_exec 1 ksymbol 1 bpf_event 1 ------------------------------------------------------------ sys_perf_event_open: pid 10318 cpu 0 group_fd -1 flags 0x8 = 14 sys_perf_event_open: pid 10318 cpu 1 group_fd -1 flags 0x8 = 15 sys_perf_event_open: pid 10318 cpu 2 group_fd -1 flags 0x8 = 16 sys_perf_event_open: pid 10318 cpu 3 group_fd -1 flags 0x8 = 17 sys_perf_event_open: pid 10318 cpu 4 group_fd -1 flags 0x8 = 18 sys_perf_event_open: pid 10318 cpu 5 group_fd -1 flags 0x8 = 19 sys_perf_event_open: pid 10318 cpu 6 group_fd -1 flags 0x8 = 20 sys_perf_event_open: pid 10318 cpu 7 group_fd -1 flags 0x8 = 21 'perf test' needs to update base-record & system-wide-dummy attr expected values for test-record-C0: 1. Because a dummy sideband event is added to the sampling of specified CPUs. When evlist contains evsel of different sample_type, evlist__config() will change the default PERF_SAMPLE_ID bit to PERF_SAMPLE_IDENTIFICATION bit. The attr sample_type expected value of base-record and system-wide-dummy in test-record-C0 needs to be updated. 2. The perf record uses evlist__add_aux_dummy() instead of evlist__add_dummy() to add a dummy event. The expected value of system-wide-dummy attr needs to be updated. The 'perf test' result is as follows: # ./perf test list 2>&1 | grep 'Setup struct perf_event_attr' 17: Setup struct perf_event_attr # ./perf test 17 17: Setup struct perf_event_attr : Ok Signed-off-by: Yang Jihong Acked-by: Adrian Hunter Tested-by: Ravi Bangoria Cc: Alexander Shishkin Cc: Andi Kleen Cc: Anshuman Khandual Cc: Ian Rogers Cc: Ingo Molnar Cc: James Clark Cc: Jiri Olsa Cc: Kan Liang Cc: Mark Rutland Cc: Namhyung Kim Cc: Peter Zijlstra Cc: Thomas Richter Link: https://lore.kernel.org/r/20230904023340.12707-4-yangjihong1@huawei.com Signed-off-by: Arnaldo Carvalho de Melo Stable-dep-of: 792bc998baf9 ("perf record: Fix debug message placement for test consumption") Signed-off-by: Sasha Levin

perf evlist: Add evlist__findnew_tracking_event() helper

2024-06-12T09:12:18+00:00

[ Upstream commit 9c95e4ef065723496442898614d09a9a916eab81 ] Currently, intel-bts, intel-pt, and arm-spe may add tracking event to the evlist. We may need to search for the tracking event for some settings. Therefore, add evlist__findnew_tracking_event() helper. If system_wide is true, evlist__findnew_tracking_event() set the cpu map of the evsel to all online CPUs. Signed-off-by: Yang Jihong Acked-by: Adrian Hunter Tested-by: Ravi Bangoria Cc: Alexander Shishkin Cc: Andi Kleen Cc: Anshuman Khandual Cc: Ian Rogers Cc: Ingo Molnar Cc: James Clark Cc: Jiri Olsa Cc: Kan Liang Cc: Mark Rutland Cc: Namhyung Kim Cc: Peter Zijlstra Cc: Thomas Richter Link: https://lore.kernel.org/r/20230904023340.12707-3-yangjihong1@huawei.com Signed-off-by: Arnaldo Carvalho de Melo Stable-dep-of: 792bc998baf9 ("perf record: Fix debug message placement for test consumption") Signed-off-by: Sasha Levin

perf record: Lazy load kernel symbols

2024-06-12T09:12:15+00:00

[ Upstream commit 1a27fc01700fbff2f205000edf0d1d315b5f85cc ] Commit 5b7ba82a75915e73 ("perf symbols: Load kernel maps before using") changed it so that loading a kernel DSO would cause the symbols for the DSO to be eagerly loaded. For 'perf record' this is overhead as the symbols won't be used. Add a field to 'struct symbol_conf' to control the behavior and disable it for 'perf record' and 'perf inject'. Reviewed-by: Adrian Hunter Signed-off-by: Ian Rogers Acked-by: Namhyung Kim Cc: Alexander Shishkin Cc: Andi Kleen Cc: Athira Jajeev Cc: Changbin Du Cc: Colin Ian King Cc: Dmitrii Dolgov <9erthalion6@gmail.com> Cc: German Gomez Cc: Huacai Chen Cc: Ingo Molnar Cc: James Clark Cc: Jiri Olsa Cc: K Prateek Nayak Cc: Kajol Jain Cc: Kan Liang Cc: Leo Yan Cc: Li Dong Cc: Liam Howlett Cc: Mark Rutland Cc: Masami Hiramatsu Cc: Miguel Ojeda Cc: Ming Wang Cc: Nick Terrell Cc: Paolo Bonzini Cc: Peter Zijlstra Cc: Ravi Bangoria Cc: Sandipan Das Cc: Sean Christopherson Cc: Steinar H. Gunderson Cc: Vincent Whitchurch Cc: Wenyu Liu Cc: Yang Jihong Link: https://lore.kernel.org/r/20231102175735.2272696-3-irogers@google.com Signed-off-by: Arnaldo Carvalho de Melo Stable-dep-of: aaf494cf483a ("perf annotate: Fix annotation_calc_lines() to pass correct address to get_srcline()") Signed-off-by: Sasha Levin

perf record: Delete session after stopping sideband thread

2024-06-12T09:12:13+00:00

[ Upstream commit 88ce0106a1f603bf360cb397e8fe293f8298fabb ] The session has a header in it which contains a perf env with bpf_progs. The bpf_progs are accessed by the sideband thread and so the sideband thread must be stopped before the session is deleted, to avoid a use after free. This error was detected by AddressSanitizer in the following: ==2054673==ERROR: AddressSanitizer: heap-use-after-free on address 0x61d000161e00 at pc 0x55769289de54 bp 0x7f9df36d4ab0 sp 0x7f9df36d4aa8 READ of size 8 at 0x61d000161e00 thread T1 #0 0x55769289de53 in __perf_env__insert_bpf_prog_info util/env.c:42 #1 0x55769289dbb1 in perf_env__insert_bpf_prog_info util/env.c:29 #2 0x557692bbae29 in perf_env__add_bpf_info util/bpf-event.c:483 #3 0x557692bbb01a in bpf_event__sb_cb util/bpf-event.c:512 #4 0x5576928b75f4 in perf_evlist__poll_thread util/sideband_evlist.c:68 #5 0x7f9df96a63eb in start_thread nptl/pthread_create.c:444 #6 0x7f9df9726a4b in clone3 ../sysdeps/unix/sysv/linux/x86_64/clone3.S:81 0x61d000161e00 is located 384 bytes inside of 2136-byte region [0x61d000161c80,0x61d0001624d8) freed by thread T0 here: #0 0x7f9dfa6d7288 in __interceptor_free libsanitizer/asan/asan_malloc_linux.cpp:52 #1 0x557692978d50 in perf_session__delete util/session.c:319 #2 0x557692673959 in __cmd_record tools/perf/builtin-record.c:2884 #3 0x55769267a9f0 in cmd_record tools/perf/builtin-record.c:4259 #4 0x55769286710c in run_builtin tools/perf/perf.c:349 #5 0x557692867678 in handle_internal_command tools/perf/perf.c:402 #6 0x557692867a40 in run_argv tools/perf/perf.c:446 #7 0x557692867fae in main tools/perf/perf.c:562 #8 0x7f9df96456c9 in __libc_start_call_main ../sysdeps/nptl/libc_start_call_main.h:58 Fixes: 657ee5531903339b ("perf evlist: Introduce side band thread") Signed-off-by: Ian Rogers Cc: Adrian Hunter Cc: Alexander Shishkin Cc: Athira Rajeev Cc: Christian Brauner Cc: Disha Goel Cc: Ingo Molnar Cc: James Clark Cc: Jiri Olsa Cc: Kajol Jain Cc: Kan Liang Cc: K Prateek Nayak Cc: Mark Rutland Cc: Namhyung Kim Cc: Peter Zijlstra Cc: Song Liu Cc: Tim Chen Cc: Yicong Yang Link: https://lore.kernel.org/r/20240301074639.2260708-1-irogers@google.com Signed-off-by: Arnaldo Carvalho de Melo Signed-off-by: Sasha Levin

perf record: Check conflict between '--timestamp-filename' option and pipe mode before recording

2024-03-26T22:19:43+00:00

[ Upstream commit 02f9b50e04812782fd006ed21c6da1c5e3e373da ] In pipe mode, no need to switch perf data output, therefore, '--timestamp-filename' option should not take effect. Check the conflict before recording and output WARNING. In this case, the check pipe mode in perf_data__switch() can be removed. Before: # perf record --timestamp-filename -o- perf test -w noploop | perf report -i- --percent-limit=1 # To display the perf.data header info, please use --header/--header-only options. # [ perf record: Woken up 1 times to write data ] [ perf record: Dump -.2024011812110182 ] # # Total Lost Samples: 0 # # Samples: 4K of event 'cycles:P' # Event count (approx.): 2176784359 # # Overhead Command Shared Object Symbol # ........ ....... .................... ...................................... # 97.83% perf perf [.] noploop # # (Tip: Print event counts in CSV format with: perf stat -x,) # After: # perf record --timestamp-filename -o- perf test -w noploop | perf report -i- --percent-limit=1 WARNING: --timestamp-filename option is not available in pipe mode. # To display the perf.data header info, please use --header/--header-only options. # [ perf record: Woken up 1 times to write data ] [ perf record: Captured and wrote 0.000 MB - ] # # Total Lost Samples: 0 # # Samples: 4K of event 'cycles:P' # Event count (approx.): 2185575421 # # Overhead Command Shared Object Symbol # ........ ....... ..................... ............................................. # 97.75% perf perf [.] noploop # # (Tip: Profiling branch (mis)predictions with: perf record -b / perf report) # Fixes: ecfd7a9c044e ("perf record: Add '--timestamp-filename' option to append timestamp to output file name") Signed-off-by: Yang Jihong Acked-by: Namhyung Kim Link: https://lore.kernel.org/r/20240119040304.3708522-3-yangjihong1@huawei.com Signed-off-by: Namhyung Kim Signed-off-by: Sasha Levin

perf top: Uniform the event name for the hybrid machine

2024-03-26T22:19:43+00:00

[ Upstream commit a61f89bf76ef6f87ec48dd90dbc73a6cf9952edc ] It's hard to distinguish the default cycles events among hybrid PMUs. For example, $ perf top Available samples 385 cycles:P 903 cycles:P The other tool, e.g., perf record, uniforms the event name and adds the hybrid PMU name before opening the event. So the events can be easily distinguished. Apply the same methodology for the perf top as well. The evlist__uniquify_name() will be invoked by both record and top. Move it to util/evlist.c With the patch: $ perf top Available samples 148 cpu_atom/cycles:P/ 1K cpu_core/cycles:P/ Reviewed-by: Ian Rogers Signed-off-by: Kan Liang Tested-by: Arnaldo Carvalho de Melo Cc: Hector Martin Cc: Marc Zyngier Cc: Mark Rutland Cc: Namhyung Kim Link: https://lore.kernel.org/r/20231214144612.1092028-2-kan.liang@linux.intel.com Signed-off-by: Arnaldo Carvalho de Melo Stable-dep-of: 02f9b50e0481 ("perf record: Check conflict between '--timestamp-filename' option and pipe mode before recording") Signed-off-by: Sasha Levin

perf record: Fix possible incorrect free in record__switch_output()

2024-03-26T22:19:43+00:00

[ Upstream commit aff10a165201f6f60cff225083ce301ad3f5d8f1 ] perf_data__switch() may not assign a legal value to 'new_filename'. In this case, 'new_filename' uses the on-stack value, which may cause a incorrect free and unexpected result. Fixes: 03724b2e9c45 ("perf record: Allow to limit number of reported perf.data files") Signed-off-by: Yang Jihong Acked-by: Namhyung Kim Link: https://lore.kernel.org/r/20240119040304.3708522-2-yangjihong1@huawei.com Signed-off-by: Namhyung Kim Signed-off-by: Sasha Levin